NBC News - The Food and Drug Administration is warning doctors against over-prescribing testosterone-boosting drugs for men, saying the popular treatments have not been established as safe or effective for common age-related issues like low libido and fatigue.

NBC News - The Food and Drug Administration is warning doctors against over-prescribing testosterone-boosting drugs for men, saying the popular treatments have not been established as safe or effective for common age-related issues like low libido and fatigue.